The present invention relates to a coke oven hopper truck or lorry car of the type supporting a lifting device which is capable of removing filling covers from the filling holes of a coke oven chamber. More particularly, the present invention is directed to such a device wherein the lifting device includes at least one rotatable and vertically displaceable cover holder.
A device of this general type is disclosed in U.S. Pat. No. 1,609,919, which discloses a coke oven lorry car or hopper truck, in connection with which the covers of a coke oven chamber to be filled with coal are lifted by means of a lifting device, and after the coke oven chamber is filled, the covers are replaced on the filling holes. The lifting device in this known arrangement employs a plurality of electromagnets as cover holders equal to the number of filling holes of the coke oven chamber. When each holder places a respective cover back into the respective filling hole, the holder is rotated about its vertical axis such that the cover is pressed downwardly by the holder and is forced to rotate against its seat in the filling hole. The intention of this operation is to provide a better seal between the cover and the filling hole frame. However, this arrangement is associated with the disadvantage of requiring a significant amount of time to carry out this seating operation. Additionally, this arrangement is associated with the further disadvantage of risk of damage to at least one of the seat surfaces during the rotation of the covers. This arrangement is additionally associated with the still further disadvantage of soiling of the roof of the coke oven chamber. Additionally, there is by no means any guarantee of achieving a tight seal between the covers and the respective surfaces of the filling holes.
Even further, in this known arrangement the removed covers are placed on the roof of the coke oven chamber. When the covers are to be replaced, it is necessary to achieve very precise positioning of the hopper truck or lorry car. Finally, there is considerable danger in this known arrangement of damaging the oven cover when depositing thereon the filling covers.